1. Field of the Invention
The present embodiments relate to a plasma display panel, and more particularly, to a plasma display panel that protects both substrates against distortion when assembled, and reduces a halation effect.
2. Description of the Related Art
Plasma display panels (PDPs) display an image by using a gas discharge. PDPs have excellent display capability in terms of display capacity, brightness, contrast, latent image, and viewing angle.
In a PDP, a front substrate, which has sustain electrodes and scan electrodes with barrier ribs interposed therebetween, is sealed against a rear substrate having address electrodes. The barrier ribs define discharge cells. An inert gas (e.g. neon (Ne) and xenon (Xe)) is filled in the discharge cells.
When an address voltage is supplied to the address electrodes, and a scan pulse is supplied to the scan electrodes, the PDP produces wall charges between the two electrodes, and selects the discharge cells to be turned on by an address discharge. In this state, when a sustain pulse is supplied to the sustain electrodes and the scan electrodes, electrons and ions formed in the sustain electrodes and the scan electrodes travel between the sustain electrodes and the scan electrodes. Accordingly, the address voltage is added to a wall voltage stemming from the wall charges formed by the address discharge. Thus, the address voltage exceeds a discharge ignition voltage, thereby generating a sustain discharge within the selected discharge cells.
A vacuum ultraviolet ray generated within the discharge cells by the sustain discharge excites a phosphor material. The phosphor material relaxes from an excited state, and thus generates a visible light beam. Accordingly, an image is formed on the PDP.
The PDP enables the sustain discharge to occur at a low voltage by forming and accumulating the wall charges. Further, in order to protect the sustain electrodes and the scan electrodes against discharge, the sustain electrodes and the scan electrodes provided across the entire surface of the front substrate are covered with a dielectric layer. The front substrate is sealed against the rear substrate, and thus barrier ribs included in the rear substrate are closely adhered to the dielectric layer, thereby defining the discharge cells.
When the front substrate and the rear substrate of the PDP are sealed against each other, the front substrate and the rear substrate are distorted due to a property of a sealant whose volume is reduced in the process of annealing the sealant adhering both substrates, a difference in the tension force of a clip fastening the both substrates, and a relatively large tension force of the clip at a vent side.
Moreover, a halation effect may occur in the PDP. The halation effect is defined as a blurred phenomenon that occurs when a visible light beam emitted from an emissive discharge cell passes over an adjacent non-emissive discharge cell.